Portable burglar-alarm.



UNITED STATES PATENT OFFICE.

LEON LEMBERG, 0F BROOKLYN, NEW YORK.

PORTABLE BURGLAR-ALARM.

Application filed. July 22, 1916.

To all whom it may concern:

Be it known that I, LEON LEMBERG; a citi- Zen of the United States, and a resident of the city of New York, borough of Brooklyn, in the county of Kings and State of New York, have invented a new and Im proved Portable Burglar-Alarm, of which the following is a full, clear, and exact de scription.

This invention relates to burglar alarms and it has for its general objects to provide a device of this character which is portable so that it can be readily set up at any place where protection against burglary is desired, the device being of simple, novel and inexpensive construction and so designed that it can be easily set up for use, and which when tripped by the opening of a door or window, or the entrance or movement of a burglar in a room, passage or compartment, will cause the giving of an alarm, which will continue to sound until the warning is heeded and the device is reset, thereby causing the burglar to be frightened away, or his apprehension.

A more specific object of the invention is the provision of a burglar device in the form of a portable box having an electric signal, circuit controlling switches, one of which is automatic, a source of current, and means for holding the automatic switch open when the device is set, such means including a string which is adapted to be connected with a door or window or to be stretched across a room or passage, so that when the string is pulled the alarm circuit will be closed to actuate the alarm. This will also occur when the string is cut or the tension is released.

With such objects in view, and others Specification of Letters Patent.

Patented Aug. 28, 1917. Serial No. 110,649. I

Fig. 3 is a detail view on the line 3-3, Fig. 1; and

Fig. 4 is a diagrammatic view of the electrical devices and circuit connections.

Referring to the drawing, 1 designates a box of suitable size and construction which is normally closed by a hinged cover 2 that may have a handle 3 for convenience in carrying the device. In the box 1 is a horizontal partition 4 which provides upper and lower compartments 5 and 6, there being battery cells 7 in the lower comparti'nent. In the upper compartment is an electric bell S or equivalent signal fastened to the upper side of the plate or partition 4, and also on the latter are switches 9 and 10 for controlling the circuit of the bell. The switch 9 has a movable contact 11 and a fixed contact 12, the movable contact being shifted into and out of closed circuit position manually when the alarm device is to be rendered operative or inoperative. The switch 10 is automatically closed and comprises a movable contact 13 and a fixed contact 14, the movable contact being connected with a spring 15 which tends to hold the contact 13 in closed circuit position. The circuit arrangement of the battery 7, bell 8 and the switches 9 and 10 is shown in Fig. 4. The movable Contact 13 of the automatically closed switch 10 is adapted to be held open by a wheel 16 journaled on the plate 4,. This wheel has a plurality of outwardly extending radial teeth 17, any one of which is adapted to engage a lug 18 on the free end of the movable contact 13. found on the wheel 16 is a cord or string 19 which passes out through an opening 20 in the wall of the box, and on the free end of the string is a ring 21 or equivalent device whereby the string can be attached to a window sash or door, so that when a burglar forces an entrance a pull will be exerted on the string, whereby the wheel 16 will be turned far enough to disengage the tooth 17 from the lever or contact 18, freeing the latter so that its spring 15 can close the bell circuit. The string 19 can be stretched across a room or passage so that the burglar in walking around will entangle his feet with the string and cause the pull thereon to release the automatic switch so that it will close and ring the bell. To facilitate the turning of the wheel 16 for winding the string a handle 22 is arranged on the wheel. Obviously, in

are in series the circuit of the bell will not be completed. In setting the device the string must be under tension so that the wheel 11 by one of its teeth will hold the movable contact of the automatic switch in open position, as shown in Fig. 1. After this is done the switch 9 is closed, whereby the device is in readiness to be tripped or set off by a burglar.

It will be understood that when the device is set the string 19 is under tension, and if this tension is released, as by opening a door or window, or by the string being cut, the alarm will be set Ofi". Thus, either a pull or a release of the string will be effective in actuating the alarm.

From the foregoing description taken in connection with the accompanying drawing, the advantages of the construction and method of operation will be readily understood by those skilled in the art to which the invention appertains, and while I have described the principle of operation, together with the device which I now consider to be the best embodiment thereof, I desire to have it understood that the device shown is merely illustrative and that such changes may be made when desired as fall within the scope of the appended claims.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1. In a device of the class described, the combination of a signal circuit switch in eluding a fixed contact and a movable contact, means tending to engage the movable contact with the fixed contact, a pull element under tension when the contacts are separated, and a device to which the element is attached normally engaging the movable contact to hold the same in open circuit position and movable out of engagement with the movable contact whether the said element is subjected to a pull or the element should break, whereby the said means actuates the movable contact to circuit-closing position.

In a device of the class described, the combination of a signal controlling switch including a fixed contact and a movable contact, a spring connected with the movable contact to urge the same into engagement with the fixed. contact, a pull cord, a drum around. which the pull cord winds, and means on the drum engageable with the movable contact for holding the same separated from the fixed contact against the tension of the said spring, said means being automatically disengageable from the movable contact when the drum is turned by an extra pull on the said cord.

3. In a device of the class described, the combination of a pull cord, a drum on which the cord is wound, teeth on the periphery of the drum, a signal. circuit controlling lever mounted adjacent the drum with its free end in the path of the teeth, and a spring operating on the lever and tending to move the same out of the path of the teeth, and the lever having a range of movement permitting the engaging tooth to move forwardly out of engagement with the lever when the cord is pulled.

LEON LEMBERG. lVitnesses JOSEPH TRUEMAN, JAKE IVEINBAUM.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

